Two fiber-optic underwater cables that were damaged Wednesday in the Mediterranean Sea near Egypt resulted in Internet traffic delays for some U.S. users trying to link to India and the Middle East.

The congestion and delay on Internet links due to the rerouting of traffic is measured in milliseconds, and while not considered dire, is noticeable, according to industry officials.

A preliminary investigation has linked the cuts to a ship's anchor that dragged and ripped into the two cables while the ship was anchored in an unusual location because of bad weather, officials said. Repairs could take days.

"Any interruption in service is important to us," said Linda Laughlin, a spokeswoman for Verizon Communications Inc. in Basking Ridge, N.J.

Because two cables were cut, the normal rerouting of Internet traffic is more complex than if only one cable had been damaged, Laughlin said. Much of the Internet traffic between the U.S. and India and nearby nations that was normally traveling through the Mediterranean is now being passed the other way around the world, crossing the Pacific Ocean, resulting in milliseconds of delay, she said.

Laughlin couldn't estimate how many milliseconds, although one India-based company put the delay at one-third of a second.

Some Verizon customers in the U.S., including government agencies and Internet service providers with thousands of their own customers, have contacted Verizon to ask about the status of repairs, Laughlin added.

Verizon is part owner with a consortium of other companies of one of the two cables that was cut, referred to as the SEA-ME-WE4, while the other is owned by Flag Telecom Group Ltd. in the U.K. Wednesday, a Flag official said repairs to that cable could take 12 to 15 days.

Laughlin said the SEA-ME-WE4 consortium was preparing a ship to make the needed repairs. A grappling hook aboard the ship will be used to find each end of the cut cable, and then bring the two parts aboard ship where they will be spliced back together with a fresh segment of optical fiber in a clean room, she said.

Some Internet traffic has been routed to a nearby Mediterranean cable known as SEA-ME-WE3, but much more of the traffic is routed the other way around the world, across the Pacific Ocean between Asia and the U.S., Laughlin said. Verizon has the ability to route traffic over 65 underwater cables. Overall, only a small portion of Verizon's customers have been affected by Wednesday's cable cuts, she said.

AT&T Inc.&#160;leases capacity on the SEA-ME-WE4, and some AT&T customers in the U.S. have been affected as well, a spokesman said Thursday. "We are expecting to see some congestion just because multiple carriers are rerouting traffic," said AT&T spokesman Michael Coe. He said AT&T is awaiting word on a definitive cause of the cable cuts and the time it will take to repair them.

India Affected

The ISP Association of India said traffic from India to the Atlantic region saw a 50% to 60% bandwidth reduction when the cables were first damaged, but others reported that reduction has been vastly improved as traffic was rerouted.

At Satyam Computer Services in Hyderabad, India, Internet traffic that used to travel through the Middle East is Thursday being routed through Singapore, resulting in as much as 350 milliseconds of Internet traffic latency, which "isn't a big problem," said a network and systems director at Satyam.

IDG News Service contributed to this report.

This story, "Cut Cables Force Worldwide 'Net Traffic Rerouting" was originally published by
Computerworld.

To comment on this article and other PCWorld content, visit our Facebook page or our Twitter feed.